The 685 Series Poppet Check Valve offers a compact, high-performance solution for controlling fluid and air flow with precision. Designed with a thin elastomer disc supported by a poppet, it seals reliably even at very low back pressure or vacuum conditions. This valve opens at a light 1/3 psi cracking pressure and features a high flow Cv of 10.2 with 1/2" NPT ends, allowing excellent throughput in a small footprint. With Buna-N O-rings and 302 stainless steel springs, the 685 Series is ideal for systems requiring chemical compatibility and responsive sealing. Made from glass-filled polypropylene, these valves handle operating pressures up to 125 psi and temperatures up to 140°F, making them suitable for applications in water, chemical processing, and air systems.
- Polypropylene
- Buna-N seals
- 302 SS Spring
- High flow rate
- Seat area open diameter: 0.438"
- Positive seal at very low back pressure or slight vacuum
- Cracking pressure: 1/3 psi
- Check mechanism: Disc poppet
- Maximum pressure: 125 psi
- Maximum temperature: 140°F